The present invention relates to a novel process for preparing 3-hydroxythiolane.
The known processes for preparing 3-hydroxythiolane are illustrated as follows.    (i) The compound is prepared by converting the amino group of L-asparagic acid into halogen atom, reducing its carboxyl groups into diol, subjecting it to cyclization reaction to prepare 3,4-epoxy-1-butanol, sulfonating said hydroxy group, and then cyclizing it with sodium sulfide (J. Org. Chem. 57, 4352 (1992)).    (ii) The compound is prepared by hydroborating 2,3-dihydrothiophene with an optically active diisopinocamphenylborane (J. Am. Chem. Soc. 108, 2049 (1986)).    (iii) The compound is prepared by reducing tetrahydrothiophen-3-one in the presence of optically active catalyst (J. Am. Chem. Soc. 115, 3318 (1993) and Tetrahedron Lett. 34, 785 (1993)).